Gaṅgeśa Upādhyāya

Gaṅgeśa Upādhyāya (fl. 14th century) was a philosopher from Mithilā in northern Bihar whose single great work, the Tattvacintāmaṇi (“The Jewel of Thought on Reality”), founded Navya-Nyāya, the “New Nyāya” — the most technically sophisticated school of logic and epistemology in pre-modern India. Where earlier Nyāya had followed the order of the sixteen categories of the Nyāya Sūtras, Gaṅgeśa reorganised the subject around the four means of valid knowledge — perception, inference, comparison and testimony — and developed a precise technical vocabulary for analysing the content of cognitions. This method spread from Mithilā to Navadvīpa in Bengal and then across India, and was adopted by scholars of grammar, law, aesthetics and theology. For five centuries, to be a serious Sanskrit intellectual meant knowing Navya-Nyāya.

The Tattvacintāmaṇi

The work has four books, one for each pramāṇa. The book on perception opens with a long discussion of whether the validity of a cognition is known intrinsically or extrinsically, defending the Nyāya view that truth is established by further confirmation, against the Mīmāṃsā view that cognitions are self-validating. The book on inference, by far the longest and most studied, is the centre of the system. Its most famous section examines vyāpti — “pervasion”, the invariable concomitance between the reason (smoke) and what is to be proved (fire). Gaṅgeśa tests and rejects one candidate definition after another (the commentarial tradition counts twenty-one “pseudo-definitions” in the section known as the Vyāptipañcaka and Siṃhavyāghra), showing how each fails for some case, before giving his own: pervasion is the reason’s co-location with the probandum, where the probandum is not the counterpositive of any absence that occurs in the locus of the reason. The book on comparison is short. The book on testimony discusses the meaning of words and sentences, the authority of the Veda and the existence of God.

The method

Navya-Nyāya’s innovation is a language for stating precisely what a cognition is about. Every cognition has a qualificand (viśeṣya), a qualifier (prakāra) and a relation (saṃsarga) between them, and each of these may be “limited” (avacchinna) by a property. In “the hill has fire”, the hill is the qualificand, fire the qualifier, contact the relation, and the qualifier is limited by fireness (vahnitva) — it is fire as fire that is cognised. Absences are analysed by their counterpositive (pratiyogin, the absentee) and the property and relation that limit it: “the absence of a pot on the floor by contact, as pot”. This apparatus allows definitions to be stated so that they apply to exactly the intended cases and no others.

Legacy

Gaṅgeśa’s son Vardhamāna and a line of Mithilā scholars continued his work; Raghunātha Śiromaṇi of Navadvīpa (c. 1475–1550) radically revised it, rejecting many Vaiśeṣika categories; Mathurānātha, Jagadīśa and Gadādhara wrote the great commentaries that became the curriculum. Modern scholars — Daniel Ingalls (Materials for the Study of Navya-Nyāya Logic, 1951), Bimal Krishna Matilal, Sibajiban Bhattacharyya, Stephen Phillips (who translated the Tattvacintāmaṇi into English) — have compared its achievements with those of Frege and Russell.